I've been getting quotes for central A/C and they all seem very high.

The basic components are available to me at the following prices:

Air Conditioning Condensing Unit Horizontal Discharge, 13 SEER,
Single-Phase, 2 Ton, R410A $1300

Evaporator: $230

Replacement furnace: $550

So the big items are about $2300 including tax. The quotes I've been
getting are around $7000.

I don't really need a new furnace, but the existing one is about 32
years old and it's so tall that to install the A/C would require a lot
of duct work to fit in the evaporator, while with a new, shorter
furnace, there is no duct work needed.

The 230V power and all the plumbing are already in place. The electrical
panel needs a circuit breaker connected to the 230V wiring that's coiled
up behind it. I need to change the furnace blower motor from plug-in to
hard-wired with a switch, which is easy to do.

Has anyone here done their own A/C install?